Image of Isis (left), also known as Aset, is by Jacqui Taliesin El Masri of Alkhemi.co.uk
We do have Egyptian Deity Posters available for sale from the Harmony Shop.
Accordng to findwords.info, in the Roman Empire, the Pelusia was a religious festival held on the 20th March to honour Isis (known as Aset to the indigenous Egyptians) and her child Harpocrates (known to the Egyptians as Heru and later called Horus by the Greeks). It would have coincided with the second day of the Quinquatria, the five-day festival dedicated to Minerva (see Blog entry for 19th March). It's not known when the tradition started because the holiday was not featured in the Roman calendar by 100 AD, but had been added by the reign of Marcus Aurelius (161–180 AD).
In the 6th Century AD, John Lydus, the Byzantine scholar, describes the festival as commemorating the mud (we would now know as the alluvial plain) caused from the flooding of the Nile. This ends hunger and drought and generates fertility. It was thought to be represented by the birth of Harpocrates, who in Roman art is depicted emerging from mud bearing a Cornucopia (rather like the image of Lar featured on the 22nd February Blog entry).
During the Pelusia, participants were sprinkled with water to obtain immunity from offenses to the gods (impunitas periurorum) and rebirth (regeneratio). The sprinkling is thought to recreate the symbolic effect of the flooding, indicating that water from the Nile itself may have been used as a form of holy water as it was in other Isis ceremonies brought to Rome. Regeneratio was also used in connection with Baptism in Christian discourse of the time.
In Egypt, the Pelusia on 20th March, marked the beginning of the sailing season. The day was under the protection of Isis and Serapis (the Graeco-Egyptian version of Osirus combined with Apis, introduced by the Ptolemies in the 1st Century BC).